There has been an air-conditioning hot-water supply combined system capable of simultaneously providing a cooling load, a heating load, and a hot water load with such a configuration that a hot water supply refrigerant block including a compressor, a water heat exchanger, an expansion device, and a refrigerant-to-refrigerant heat exchanger is cascade-connected to part of a condenser of an air conditioning refrigerant block including a compressor, a cooling/heating switching valve, an outdoor heat exchanger, an expansion device, a plurality of indoor heat exchangers, and an accumulator. In such an air-conditioning hot-water supply combined system, it has been proposed such that heat discharged from the air conditioning refrigerant block is supplied to the hot water supply refrigerant block so that operation is carried out with high efficiently (refer to Patent Literature 1 and Patent Literature 2, for example).